ARM: dts: msm: switch to RPMh controlled PMIC regulators for sdm845

Replace the stub-regulator device nodes for the PM8998, PMI8998,
and PM8005 regulators with rpmh-regulator device nodes.  This
ensures that consumers are able to modify the physical state
of these PMIC regulators.

Change-Id: Ifbb8943f9fd827b04a6077cc9150427091cb7671
CRs-Fixed: 1082230
Signed-off-by: David Collins <collinsd@codeaurora.org>